GTMAT Quadro 15 sqft Automotive Four Layer Foam Damper Dampening Deadening Resonance Dampening Super Thick &ndash; Noise Sound Deadener Installation Kit Includes: 15sqft Sheets (12" x 12"), Instruction Sheet, Degreaser, GTMAT Decals Package Includes 15 sqft (15 Sheets of 12 x 12 Sheet) GTMAT Quadro, Wooden Application Roller, GTMAT Degreaser, 2 GTMAT Decals, Easy to follow Installation Instructions, Toll Free Tech Support Layer 1 - 3/16" Foam damping Material - This additional layer of damping material helps to reduce back wave and increase overall acoustic isolation and thermal insulation. Layer 2 - 60 Mil Butyl Layer - This butyl layer absorbs the vibrations of the aluminum layer with which its in contact. It provides additional damping and decouples the aluminum layer from the foam layer. This layer also provides the bond between the foam and aluminum layers. Layer 3 - 4 Mil Aluminum Layer - This aluminum constraining layer helps to mold and conform to interior surfaces. Additionally, this layer helps to increase the damping performance of the Butyl Layer as well as reduces undesired vibrations. Layer 4 - 60 Mil Butyl Layer - This self-adhesive butyl layer absorbs the vibrations of the surface with which its in contact. It provides damping and decouples the contact layer (IE: Metal, Wood, etc...) from the aluminum layer.